Making silly mistakes and checking work

[sittinginthesun]

Just a bit of advice please re: DS1 (Year 4).

There is a huge amount of peer pressure locally to sign up with a tutor for the secondary entrance exams, but having looked into it, we have decided not to and prepare at home.

I bought the Bond pack, did the first assessment for maths and we tried a few non verbal reasoning papers.

It is completely obvious that DS gets the questions, and can answer them all correctly, but he makes silly mistakes.

It's exactly the same with his maths homework from school - he understand the concepts, can answer the questions, but will then make a mistake and switch two digits, or miscalculate an easy sum. If you point out the answer is wrong, he gets the correct answer straight away, but seems unable to check his own work, even though he has time.

Any hints or ideas on how to improve this? MN could be saving me a fortune on a tutor here.

[ReadytoOrderSir]

Reward him for checking. Insist he does the 'inverse operation' for each calculation (so if it was addition, he checks it by subtracting). Praise and reward for the checking until it becomes second nature.

Works with my yr 4 class, who quickly twigged that I gave house points for showing working out and checking, rather than purely accurate answers.

[Lonecatwithkitten]

The checking of work is a skill that you need to learn. I have to add really solid immediate recall of times tables is very useful to this skill as gives 'gut' feel as to whether answer is right or wrong.
Then reward for taking time and checking work.

[sittinginthesun]

Thank you!

I'm just trying to work out how to "teach" or practice this skill? Shall I ask him to go right back over his home work again, and do the questions from cold? Or would you do each question twice each time?

I have a similar problem, and drive my book keeper mad at work as I switch digits. But I make extra time to double check calculations.

[noblegiraffe]

Can you check his work, and tell him how many he got wrong, but not tell him which ones? Then he would have to go back through them all to spot his errors, and he might get quicker at noticing common mistakes. You could then do it again until he gets them all right.
You could time him on how long it takes him to get 100% correct - note his times down and make it competitive, see if he can beat his score. He'll hopefully get in the habit of a quick check first time around.

[sittinginthesun]

Ah, that sounds a good plan! Anything with an element of competition always goes down well.

[ReadytoOrderSir]

The trick to checking is to do it differently the second time, rather than repeat the same method and risk repeating the same error.

If the question was "What's eight bananas add three bananas?" (ie addition) and he's done 8+3=10, then he should check by doing subtraction. 10-8= oh no, that's not 3 so I must have gone wrong.

Rounding is also very handy to make an estimate of the answer before you solve it. 26x8 is going to be similar to 25x8=200. If he gets an answer of 2008, then it must be wrong because it's so far off the estimate.

[Blueskiesandbuttercups]

Exactly the same scenario here,same age,not paying for a tutor,silly mistakes.

We were doing maths word problems which he keeps doing in his head without writing down the working in order to ensure no silly mistakes.

We were thinking of doing harder problems so he has to slow down and can't do them in his head.